You might have seen the recent news reports about the collision between U.S. and Russian communication satellites. The U.S. satellite was one of the Iridium satellites. What wasn’t reported and you probably don’t know is that an object database management system (ODBMS) is an important part of the Iridium system. Even though ODBMSs are a [...]
February 13, 2009
I am now also posting on the Cutter Blog. My initial posting is (The Acronym) SOA is (Perhaps) Dead (at Some Companies); Long Live Services. It is a response to Anne Thomas Manes’ SOA is Dead; Long Live Services on her blog at the Burton Group.
January 9, 2009
The typical definition of an atomic task or process is one that cannot be decomposed further. This is vague and subject to interpretation. The Decomposition Matrix on this site uses a specific definition: A task (for business process diagrams) or a process (for data flow diagrams) is atomic if every input relates to every output [...]
December 3, 2008
My last posting referenced the criteria for a well-formed business process diagram mentioned in Business Process Driven SOA using BPMN and BPEL by Matjaz B. Juric and Kapil Pant. I am going to expand on their criteria to create a more comprehensive definition of a well-formed business process diagram. To start, here are three criteria [...]
November 18, 2008
I recently received two new books on business process modeling. Both books looked interesting because they had great titles. As it turns out, one book is great and the other not so good. The not so good book is Business Process Driven SOA using BPMN and BPEL by Matjaz B. Juric and Kapil Pant. There [...]
October 9, 2008
The Design Decomposition Blog is written by Doug Barry.
The relational model used the basic concept of a relation or table. The
columns or fields in the table identify the attributes such as name, age, and
so. A tuple or row contains all the data of a single instance of the table such
as a person named Doug. In the relational model, every tuple must have a unique
identification or key based on the data. In this figure, a social security
account number (SSAN) is the key that uniquely identifies each tuple in the
relation. Often, keys are used to join data from two or more relations based on
matching identification. The relational model also includes concepts such as
foreign keys, which are primary keys in one relation that re kept in another
relation to allow for the joining of data. As an example of foreign keys is
storing your mother's and father's SSAN in the tuple that represent you. Your
parents' SSANs are keys for the tuples that represent them and they are foreign
keys in the the tuple that represents you.
There are nearly 400 pages of articles on this site with over 40 pages on database concepts and standards.
Search this site for more articles
Custom Search
Browse this site for more articles
Click on the topics below to browse the articles on this site. You can see more detail by clicking on the arrows. This highlights the location of the current
article: Relational model concepts.
Related recent articles from Google News
10 things you should know about NoSQL databases TechRepublic (blog) The relational database model has prevailed for decades, but a new type of database — known as NoSQL — is gaining attention in the enterprise. ... 26 Aug 2010 at 10:36am
Microsoft Office 2010 - The Best New Features in Access Boosh News (press release) (blog) Information stored in spreadsheets and documents can be easier to understand and less time consuming to manage in a relational database model. ... and more » 25 Aug 2010 at 1:20am
Database Design for Mere Mortals(R): A Hands-On Guide to Relational Database Design (2nd Edition) by Michael J. Hernandez Average Customer Review: based on 127 reviews. Customer Review: This book was just the text I was looking for as a n00b data base designer looking to build a data base for a pet project of mine. I'm a forester and forest planner, not a computer specialist. Thus, I needed instruction from the ground up, and this book fit the bill. Some specific praise: First, the book bridged the gap between adm...
Understanding Relational Database Query Languages by Suzanne W Dietrich Average Customer Review: based on 2 reviews. Customer Review: I like this book. I was looking for a book that gave the "why" behind SQL. I graduated years ago with a Computer Science degree and didn't have the opportunity to take a database class. I found myself having to learn SQL on the job. This book uncovers the mystery of SQL's behavior. It has a lot of examples that are supported by the s...
Database in Depth: Relational Theory for Practitioners by C.J. Date Average Customer Review: based on 22 reviews. Customer Review: C.J. Date is the expert on relational databases. This is a great book I use it in my Systems Analysis and Design Class.
based on 127 reviews.
based on 2 reviews.
